Spectrum Sharing Models in Cognitive Radio Networks

Spectrum scarcity demands thinking new ways to manage the distribution of radio frequency bands so that its use is more effective. The emerging technology that can enable this paradigm shift is the cognitive radio. Different models for organizing and managing cognitive radios have emerged, all with specific strategic purposes. In this article we review the allocation spectrum patterns of cognitive radio networks and analyse which are the common basis of each model. We expose the vulnerabilities and open challenges that still threaten the adoption and exploitation of cognitive radios for open civil networks.